The present invention relates generally to hinge structures, and more particularly to a security hinge construction wherein there is employed a concealed electrical component such as a switch, which can be wired into an external electrical circuit to provide an indication at a monitoring panel or the like, as to the relative position of the door, viz., whether it is closed, fully opened, or partially open.
In many situations, such as building security, fire safety, environmental control and the like it is desirable to monitor doors in a building or structure so as to provide some indication as to their condition. For example, it may be desired to know whether the door is fully closed, fully open, or even ajar somewhat.
Hinge constructions have been employed wherein a switch or the like was mounted directly to the hinge leaves, as for example in U.S. Pat. Nos. 3,729,603; 3,715,537; 3,803,375; 4,066,857; 4,049,934 and British Pat. No. 1,279,381. These prior art arrangements, though useful for some purposes, fail to meet the requirements of certain security situations, as in certain of the prior art designs the switches, wires and switch actuating members were generally exposed at some point during the operation of the associated door. It will be appreciated that one desirable characteristic of a security type hinge is concealment of the switch and associated elements, so as to give no external indication of the nature of the security hinge, but on the contrary, provide a conventional looking hinge exterior appearance. In others, while the switch is concealed, it is not effectively sealed against the entry of moisture.
As a further matter, it is also desirable, as briefly indicated above, to provide such a hinge actuated switch arrangement which is capable of providing an indication for several different conditions of the associated door. Accordingly, a desirable feature of such a security hinge is its adaptability to a desired use, in providing a suitable indication only at the desired point of door movement in each particular application.
Moreover, with the introduction of electrical components such as a switch into a pivotally movable hinged structure, it is important to assure that wires, leads, or the like exiting the structure will not be impinged upon or otherwise disturbed during operation of the hinge, to insure the integrety of the electrical circuit connections required for proper operation of the device. Also in connection with insuring reliable electrical operation of the device, it is desirable to provide such a switch arrangement which is adapted for effectively sealing the electrical components against intrusion by moisture or the like. This latter consideration is also important in obtaining approval of rating agencies such as Underwriters Laboratories.
Accordingly it is a general object of this invention to provide a new and improved security hinge construction adapted to provide an indication as to the opening and closing or relative position therebetween of an associated door member.
A more specific object of this invention is to provide a hinge construction with an improved operating arrangement, and which arrangement is selectively adjustable for use in a variety of applications, wherein such indication is to be given for different relative positions of an associated door.
A further object of this invention is to provide a hinge construction of the type described wherein the electrical components are sealed against intrusion by moisture or the like, without regard for the relative orientation or mounting position of the hinge structure upon its door.
Yet another object of this invention is to provide a hinge construction of the type described which is further adapted to protect the electrical components and connections to external devices against mechanical wear, abrasion, or the like, so as to provide a relatively long service life without regard to the frequency of operation of the associated door.
Briefly, and in accordance with the foregoing, a hinge structure is provided which includes, first and second pivotally connected hinge leaves, each leaf including at least one knuckle disposed adjacent to and pivotally movable relative to the knuckle on the other leaf, an electrical circuit component including actuator means carried by one of said leaves, and capable of producing a change in an output condition thereof, operating means carried by the other of said hinge leaves for operating said actuator means in response to relative movement between said hinge leaves to produce said change in condition of said electrical component, and sealing means for effectively sealing the knuckle interface thus protecting said electrical circuit component against intrusion of moisture or the like, substantially without regard to the relative orientation or mounting position of said hinge construction. Further, there is provided an improved operating means employing an offset piston arranged for operating said plunger and increasing the sensitivity of said hinge to relative movement.
Other objects, features and advantages of this invention will become more readily apparent upon consideration of the following detailed description together with the accompanying drawings.